US3509861A

US3509861A - Internal combustion engine

Info

Publication number: US3509861A
Application number: US737167A
Authority: US
Inventors: Herbert Deutschmann; Jurgen Wahnschaffe; Wolfgang Rudert; Herbert Mader
Original assignee: Daimler Benz AG
Current assignee: Daimler Benz AG
Priority date: 1967-06-15
Filing date: 1968-06-14
Publication date: 1970-05-05
Anticipated expiration: 1987-05-05

Description

y 5 1970 H. DEUTSCHMANN 1-rrm.

INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet 1 Filed June 14, 1968 INVENTORS HERBERT DEUTSCHMANN JUERGEN WAHNSCHAFFE BY WOLFGANG RUDERT vno s ATTORNEYS May 1970 H. DEU'ESCHMANN E 'AL 3,509,861

INTERNAL COMBUSTION ENGINE INVEN'IORS HERBERT DEUTSCHMANN JUERGEN VIAHNSCHAFFE BY WOLFGANG RUDERT HERBERT MAUER ATTORNEYS United States Patent O 1,576,35 Int. C1. Flm 1/10;F16n 39/06 U.S. C]. 123196 15 Claims ABSTRACT OF THE DISCLOSURE An internal combustion engine in which the lubricant line system between the crankcase and the suction pump for the lubricant has a line portion which determines the level at which a gas-free suction can be obtained; the upper edge 0f the free lubricant flow cross section is arranged in this line portion lower than the corresponding edge at the sieve for cleaning the lubricant to be sucked 01T.

The present invention relates to an internal cornbustion engine, and more particularly to a line system be tween the sump of the crankcase and the suction pump for the lubricant.

The aim underlying the present invention essentiafly resides in being able to get along wtih a 10W lubricant level in the crankcase of an internal combustion engine, especially having a dry-sump lubrication, so that the bottom part of the crankcase can be designed lower, i.e., of lesser height. This particularly flat construction of the crankcase of an internal combustion engine is required, for example, for the drive unit in modern combattype vehicles. Notwithstanding the 10W type of construction, a sufliciently large sieve cross section for the cleaning of the lubricant to be sucked out of the sump has to be available.

The underlying roblems are solved according to the present invention in that the lubricant line system between the sump of the crankcase and the lubricant suction pump includes a line section or line ortion, determining the level for a gas-free sucking-ofi of the lubricant, in which the upper edge of the free lubricant passage cross section is arranged lower than the corresponding edge at the sieve for the cleaning of the lubricant to be sucked off. The advantage is achieved by the present invention that it is possible even with a minirnum lubricant level in the crankcase to provide gas-free suct1on.

In one embodiment of the present invention, the leveldetermining line section or line portion may be arranged in the suction channel of the crankcase. Fo-r this purpose, the suction channel may be provided at its upper wall part With a downwardly directed projection.

With this embodiment, the sieve can close as cover- 0r lid-like body the discharge aperture of the lubricant line system on the side of the sump and may be designed suitably large within the frame of the available space, independently of the type of construction of the leveldetermining line portion.

According to another feature of the present invention, it is proposed that the level-determining line section is constituted by a suction connection enlarged in cross section in a funnel-like manner, in which the lower aperture terminates in the sump and the higher aperture is connected to the lubricant line system. The advantage results from such an arrangement that the sump level can be kept particularly 10W by the flat design of the aperture 0f the suction connection on the side of the sump without the drawback of sucking otf any air. A further advantage of this proposed construction according to the present invention resides in that the aperture of the suction connection on the sump side can be arranged within a part of the lubricant sump, that is relatively calm and quieted from a streamline or flow point 0f view so that the pressure losses of the pump are reduced.

In order to be able to accommodate particularly large sieve surfaces, the sieve body for the cleaning Of the lubricant to be sucked off can be arranged at an inclination to the level of the lubricant sump.

Appropriately, the sieve is arranged downstream of the suction connection and can then be secured together with the suction connection at the crankcase.

It is further proposed according to the present inven tion that the aperture of the suction connection terminating in the sump extends in the shape of a circular arc. If one arranges the connecting place of the suction line at the suction connection in the center point or in proximity to the center point of the imaginary arc, then a very even and uniform suction effect is achieved within every area of the aperture on the side of the sump.

Accordingly, it is an object of the present invention to provide an internal combustion engine With sump lubrication that avoids the aforementioned shortcomings and drawbacks encountered in the prior art by simple and operationally reliable meana Another object of the present invention resides in an internal combustion engine which is able to operate with a relatively 10W lubricant level in the crankcase in order to be able to reduce the height of the bottom part of the crankcase.

A further object of the present invention resides in an internal combustion engine of the type described above which makes available a sufliciently large sieve cross section for the cleaning of the lubricant to be sucked out of the sump.

Still another object of the present invention resides in a lubricating system for internal combustion engines in which a gas-free suction can be achieved even with a minimal lubricant level in the crankcase.

A still further object of the present invention resides in an internal comb1istion engine with sump lubrication in which pressure losses of the suction pump can be effectively reduced.

These and further objects of the present invention Will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments of suction places in crankcases With drysump lubrication according to the present invention and wherein:

FIG. 1 is a partial longitudinal cross-sectional view through the end on the flywheel side of a crankcase bottom part in accordance with the present invention;

FIG. 2 is an elevational view taken in the direction of arrow II of FIG. 1;

FIG. 3 is a partial cross-sectional view through a modified embodiment of the end on the flywheel side of a crankcase bottom part in accordance With the present invention;

FIG. 4 is a schematic plan view of the end on the flywheel side 0f a still further modified embodiment of a crankcase bottom part according to the present invention;

FIG. 5 is a plan view on the suction connection as individual part of the arrangement according to FIG. 4; and

FIG. 6 is a side elevational view of the suction place 3 illustratedin FIG. 4 and taken in the direction of arrow VI.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGS. 1 and 2, reference numeral 100 generally designates therein The front end on the flywheel side of the crankcase bottom part which includes the housing end Wall 102 and the housing bottom 103. A lubricant suction channel 101 is cast integral with the housing end Wall 102 and the hausing bottom 103 and extends transversely to the housing longitudinal axis. The suction channel 101 includes at its upper Wall part 104 a downwardly directed projection 105. The oil sump wetting the housing bottom 103 is delimited by a transverse Wall generally designated =by reference numeral 106 of the suction channel 101 which is inclined to the level of the oil sump at least in the normal position of the crankcase. The suction channel 101 is in communication With the oil sump by way of a funnelshaped channel aperture 107. The inner discharge 108 of the channel aperture 107 is delimited in the upward direction by the bottom edge 109 of the projection 105. A minimum oil level S is given by the bottom edge 109, with which oil can be sucked out of the sump essentially without sucking out any aiI-, gasor vapor-particles.

The outer discharge 110 of the channel aperture 107 is delimited in the upward direction by an edge 111 whose significance Will be further explained in the following description.

The outer discharge aperture 110 is adapted to be covered by a sive body, essentially Z-shaped in cross section, which is indicated in dash and dot lines at 112 and is t be secured at the Wall part 106 at 113 by means of bolts (not shown).

The free lubricant passage or flow cross section of the sieve body 112 is defined or delimited in the upward direction by the edge 111, whence an oil level S is determined.

Since the edge 109 according to the present invention is arranged lower than the edge 111, an ever-increasing sieve surface for the passage of the oil to be sucked off is available with an oil level increasing between S and S This. action is independent from the arrangement of the sieve body 112 both with respect to the oil level as also with respect to the projection 105. This means, the sieve body 112 can be arranged, on the one band, either perpendicularly or also inclined to the oil level and, on the other, either upstream or downstream of the level-determining projection 105.

In the embodiment according to FIG. 3, which is similar to that of FIGS. 1 and 2, the crankcase bottom part generally designated by reference numeral 300 together with the cast-on suction channel 301 is indicated only in dash and dot lines.

The oil sump wetting the housing bottom 303 is in communication With the suction channel 301 by way of a suction connection enlarged in a funnel-like manner and generally designated by reference numeral 314, of a sieve body 312 essentially X-shaped in cross section, and by way of a channel aperture 307. The cross section of the channel 301 is delimited by the housing end Wall 302, The housing bottom 303, an upper Wall part 304, as well as a transverse wall generally designated by reference numeral 306 and arranged inclined to the oil level. The suction connection 314 together witl1 the sieve body 312 can be secured in a fluid-tight manner at the channel Wall 306 at 313 by means of bolts. The lower aperture 315 of the suction connection 314 which is also smaller in cross section, terminates in the oil sump Whereas the larger aperture 316 of the connection 314 is in communication with the channel aperture 307. The upper edge 317 of the smaller, lower aperture 315 on the side of the sump in the suction connection 314 determines the lowest oil level S at which an air or gas-free suckingoil of the oil is assured.

The upper boundary of the free assage 01' flow cross section in the sieve body 312 is indicated by reference numeral 318. An oil level S corresponds to the level of this edge 318. When the oil level increases between the pegs S and S an ever-increasing sieve surface is available for the cleaning of the oil to be sucked off. In this embodiment, the suction connection 314 is arranged upstream 0f the sieve body 312. In order to be able to accommodate a particularly large sieve surface within the available 10W interior space of the crankcase bottom part 300, the sieve body 312 is again arranged inclined to the oil level in the normal position. The prevailing oil level is thereby to be assumed to extend normally substantiafly horizontally.

In the embodiment of FIGS. 4 to 6, the crankcase bottom part is generally designated by reference numeral 400, the cast-on suction channel by reference numeral 401, the housing end Wall by reference numeral 402, and the housing bottom by reference numeral 403.

The oil sump wetting the housing bottom 403 is in communication with the suction channel 401 by way of asuction connection 414 enlarged in a funnel-like manner, of a sieve body 412 essentiafly Z-shaped in cross section and by way of a channel aperture 407.

The cross section of the suction channel 401, in addition to being delimited by the end Wall 402 and the housing bottom 403, is additionally delimited by an upper channel Wall 404 and by a channel Wall 406 inclined to the oil level and provided With the channel aperture 407.

The suction connection 414 together with the sieve body 412 can be secured in a fluid-tight manner at the channel Wall 406 at 413 by rneans of b0lts (not shown). The lower aperture 415 of the suction connection 414 extends along a circular arc a and terminates in the oil sump whereas the higher aperture 416 of the connection 414 is in communication with the channel aperture 407. The center point of the arc a is located in proximity to that part of the discharge place of the lubricant at the suction connection which is disposed closest to the suction pump in the direction of flow.

The diifering pressure conditions at the sieve surface can be equalized by this type of construction of the suction connection 414. For the Same reason, that part of the aperture 415 on the side of the sump can be increased which is disposed in proximity to the area of the sieve body 412 located farthest removed from the mentioned center point. The suction pressure of the lubricant pump is considerably lower within this area cf the sieve body 412. As a result of the enlarged aperture area of the suction connection 414 on the side of the sump, this pressure decrease is then properly taken into consideration for purposes of achieving a uniform oil suction eflect.

As can be readily seen from FIG. 6, the lowest oil level S is determined by the upper edge 417 of the aperture 415 on the side of the sump with which an airfree suction of the lubricant is still assured. The upper. edge 418 of the free flow cross section at the sieve body 412 determines an oil level S Since the edge 417 is again arranged lower than the edge 418, a larger sieve cross section is available for the cleaning of the sucked off lubricant. When the oil level increases between IS and S the sieve cross section traversed by the oil also increases.

While we have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is suscepble of numerous changes and modifications as known to a person skilled in the art.

Wo claim:

1. An internal co=mbustion engine with a crankcase and a lubricant suction pump, wherein the improvement comprises lubricant line means between the sump of the crankcase and the lubricant suction pump which includes sieve means for cleaning the lubricant to be sucked off and means for determining the level for [a substantially gasfree suction operation, said level-determining means being located in a suction channel means of the crankcase and providing in effect a free lubricant flow cross-section having an upper edge which is arranged lwer than the corresponding edge at said sieve means.

2. An internal combustion engine with a crankcase and a lubricant suction pump, wherein the improvement comprises lubricant line means between the sump of the crankcase and the lubricant suction pump which includes sieve means for cleaning the lubricant to be sucked off and means for determining the level for a substantially gasfree suction operation, said level-determining means being formed, at least in part, by a suction connection enlarged in a funnel-like manner and having lower and upper apertures, the lower aperture terminating in the sump and the upper aperture being connected with said lubricant line means.

3. An internal combustion engine according to claim l, wherein said suction channel means of the crankcase includes an upper wall part having a downwardly directed projection.

4. An internal combustion engine according to claim 1, wherein the discharge of the lubricant line means to the sump is formed by a very W aperture which is very wide in relation to its height.

5. An internal combustion engine according to claim 2, wherein the body of sieve means for the cleaning of the lubricant to be sucked off is arranged at an inclination to the level of the lubricant sump in normal position.

6. An internal combustion engine according to claim 5, wherein the sieve means is arranged downstream of the suction connection.

7. An internal combustion engine according to claim 6, wherein the aperture of the suction connection discharging in the sump extends in the form of a substantially circular arc.

8. An internal combustion engine according to claim 7, wherein said line portion is arranged in a suction channel means of the crankcase.

9. An internal combustion engine according to claim l, Wherein the body of sieve means for the cleaning of the lubricant to be sucked 011 is arranged at an inclination to the level of the lubricant sump in normal osition.

10. An internal combustion engine according to claim 2, wherein the sieve means is arranged downstream of the suction connection.

11. An internal combustion engine according to claim 10, wherein the aperture of the suction connection discharging in the sump extends in the form of a substantially circular arc.

12. An internal combustion engine according to claim 11, wherein the discharge of the lubricant line means to the sump is formed by a very 10W aperture which is very wide in relation to its height.

13. An internal combustion engine according to claim 2, wherein the aperture of the suction connection discharging in the sump extends in the form of a substantially circular arc.

14. An internal combustion engine according to claim 2, wherein the discharge of the lubricant line means to the sump is formed by a very 10W aperture which is very wide in relation to its height.

15. An internal combustion engine according to claim 4, wherein said suction channel means cf the crankcase includes an upper wall part having a downwardly directed projection.

References Cited UNITED STATES PATENTS 1638,281 8/1927 Winslow et a1 I846 1'903005 3/1933 McCuen 184--6 1939765 12/1933 Church I846 2192438 3/1940 Gulick 184-6 2536,663 1/1951 Schaer 184-6 XR 3,056501 10/1962 Thorman et a1. 123-196 XR 3,143,187 8/1964 Stefan I846 MILTON KAUFMAN, Primary Examiner M. A. ANTONAKAS, Assistant Examiner U.S. C1. X.R. I846